"Still, Firefox OS could have a big impact on the Web even if it never gains significant market share. By pushing the Web forward, Mozilla is helping to ensure that mobile websites will continue to be relevant even as developers create hundreds of thousands of proprietary apps. Firefox could lose the battle for the smartphone OS market but still win the war for open standards."

I think the review kind of speaks volumes, Mozilla can make the base apps great, but the third party apps kind of stink due to the hosting being unreliable. With Ios and android there is a limit to how bad an application can be, with firefox it doesn't look like there will be a limit.

Those aren't proper apps, per se. They're not much more than IFRAMEs pointed at mobile sites.

Proper apps can use AppCache to store the entire UI in the phone and then just XMLHttpRequest or WebSocket data back and forth.